The present invention relates to a novel 2,2-(diaryl)vinylphosphine compound and a palladium-phosphine catalyst obtained by causing a palladium compound to act on the 2,2-(diaryl)vinylphosphine compound. The invention further relates to a process for obtaining an arylamine, a diaryl and an arylalkyne in the presence of the palladium-phosphine catalyst.
Many transition metal complexes have conventionally been used as catalysts for organic synthesis reactions. Phosphine compounds play an extremely important role as ligands required of these catalysts. For example, in Tsuji-Trost reaction, in which an allyl compound reacts with a nucleating agent with the aid of a palladium catalyst, phosphine compounds including triphenylphosphine function to stabilize the catalyst and accelerate the reaction (see Jiro Tsuji, Palladium Reagents and Catalysts, JOHN WILEY and SONS, 1995, pp. 125-188, pp. 290-340).
In recent years, S. L. Buchwald et al. disclosed a method for synthesizing an arylamine by the amination reaction of an aryl compound having a leaving group (see U.S. Pat. No. 5,576,460, International Publication 2000/02887, and S.L. Buchwald et al., J. Org. Chem., 2000, 65, pp. 1158-1174). Also disclosed is a process for arylamine production which is characterized by using a catalyst comprising a trialkylphosphine and a palladium compound (see JP-A-10-139742). (The term xe2x80x9cJP-Axe2x80x9d as used herein means an xe2x80x9cunexamined published Japanese patent applicationxe2x80x9d.)
Also disclosed is a method for synthesizing a diaryl compound by the carbon-carbon bond formation reaction of an aryl compound having a leaving group with an arylboric acid compound or an arylborate ester compound (see A. F. Littke et al., J. Am. Chem. Soc., 2000, 122, pp. 4020-4028, D. Z. Adriano et al., Tetrahedron Letters, 2000, 41, pp. 8199-8202, and N. Miyaura and A. Suzuki, Chem. Rev., 1995, 95, pp. 2457-2483).
Furthermore disclosed is a method for synthesizing an arylalkyne by the carbon-carbon bond formation reaction of an aryl compound having a leaving group with an alkyne compound (see H-F. Chow et al., J. Org. Chem., 2001, 66, pp. 1910-1913, Y. Nishihara et al., J. Org. Chem., 2000, 65, pp. 1780-1787, J-F. Nguefack et al., Tetrahedron Letters, 1996, 37, pp. 5527-5530, and N. A. Bumagin et al., Tetrahedron Letters, 1996, 37, pp. 897-900).
Although it is important to constitute an optimal catalyst according to the intended reaction or the substrate to be reacted, there can be a variety of complicated combinations of catalyst components, i.e., a metal and a phosphine ligand. Consequently, there are cases where even when phosphine ligands which have been developed so far are used, the catalysts are insufficient in catalytic activity, etc. and hence pose a problem when subjected to practical use in industrial reactions. It is therefore important to develop a novel phosphine ligand.
An object of the invention is to provide a novel ligand useful in various catalytic reactions. Another object of the invention is to provide a process for producing an arylamine, a diaryl and an arylalkyne important as an intermediate for medicines and agricultural chemicals and as an organic electronic material using a catalyst containing the ligand.
In order to achieve the above objects, the present inventors made extensive studies. As a result, it has been found that a novel 2,2-(diaryl)vinylphosphine compound. Furthermore, it has been found that a catalyst prepared from this 2,2-(diaryl)vinylphosphine compound and a palladium compound is effective in the amination reaction of an aryl compound having a leaving group, the carbon-carbon bond formation reaction of an aryl compound having a leaving group with an arylboric acid compound or an arylborate ester compound, and the carbon-carbon bond formation reaction of an aryl compound having a leaving group with an alkyne compound, and enables an arylamine, a diaryl and an arylalkyne to be produced efficiently in a short time period. The invention has been completed based on this finding.
The invention includes the following.
1. A 2,2-(diaryl)vinylphosphine compound represented by the following general formula (1): 
(wherein R1 is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alicyclic group having 5 to 7 carbon atoms, or a phenyl group which may have one or more substituents; R2 and R3 may be the same or different and each is an alkyl group having 1 to 6 carbon atoms, an alicyclic group having 5 to 7 carbon atoms, or a phenyl group which may have one or more substituents; R4, R5, R6, and R7 may be the same or different and each is an alkyl group having 1 to 6 carbon atoms, an alicyclic group having 5 to 7 carbon atoms, a phenyl group which may have one or more substituents, an alkoxy group having 1 to 6 carbon atoms, a dialkylamino group having 1 to 3 carbon atoms, a halogen atom, a benzyl group, a naphthyl group, or a halogen-substituted lower alkyl group having 1 or 2 carbon atoms, provided that R4 and R5 taken together and/or R6 and R7 taken together may represent a fused benzene ring, a substituted fused benzene ring, a trimethylene group, a tetramethylene group, or a methylenedioxy group; and p, q, r, and s each is 0 to 5, provided that p+q and r+s each is in the range of from 0 to 5).
2. A palladium-phosphine catalyst obtained by causing a palladium compound to act on the 2,2-(diaryl)vinylphosphine compound described in 1 above.
3. The palladium-phosphine catalyst described in 2 above wherein the palladium compound is a salt or complex of palladium having a valence of 4, 2, or 0.
4. A process for producing an arylamine which comprises using the palladium-phosphine catalyst described in 2 or 3 above in the amination reaction of an aryl compound represented by the following general formula (2):
ArX1xe2x80x83xe2x80x83(2)
(wherein Ar is an aryl group which may have one or more substituents, or a heteroaryl group which may have one or more substituents; and X1 is a halogen atom, a trifluoromethanesulfonyloxy group, a methanesulfonyloxy group, or a toluenesulfonyloxy group) with an amine compound in the presence of a base.
5. A process for producing a diaryl which comprises using the palladium-phosphine catalyst described in 2 or 3 above in the carbon-carbon bond formation reaction of an aryl compound represented by the following general formula (2)
ArX1xe2x80x83xe2x80x83(2)
(wherein Ar and X1 have the same meanings as defined above with an arylboric acid compound or an arylborate ester compound in the presence of a base).
6. A process for producing an arylalkyne which comprises using the palladium-phosphine catalyst described in 2 or 3 above in the carbon-carbon bond formation reaction of an aryl compound represented by the following general formula (2)
ArX1xe2x80x83xe2x80x83(2)
(wherein Ar and X1 have the same meanings as defined above with an alkyne compound in the presence of a base).
The invention will be explained below in detail.
In the compound (1) of the invention, R1 is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alicyclic group having 5 to 7 carbon atoms, or a phenyl group which may have one or more substituents. R1 is preferably a hydrogen atom, a lower alkyl group having 1 to 3 carbon atoms, an alicyclic group having 6 carbon atoms, or a phenyl group.
Specific examples of R1 include a hydrogen atom; an alkyl group having 1 to 6 carbon atoms, such as methyl, ethyl, propyl, isopropyl, n-butyl, tert-butyl, isobutyl, sec-butyl, pentyl, or hexyl; an alicyclic group having 5 to 7 carbon atoms, such as cyclopentyl, cyclohexyl or cycloheptyl; a phenyl group which may have one or more substitutents, for example, a lower alkyl group having 1 to 4 carbon atoms, such as methyl, ethyl, propyl, isopropyl, n-butyl, tert-butyl, isobutyl or sec-butyl, a lower alkoxy group having 1 to 4 carbon atoms, such as methoxy, ethoxy, propoxy or butoxy, a di(lower alkyl)amino group in which each alkyl has 1 to 3 carbon atoms, such as dimethylamino, diethylamino or dipropylamino, or a halogen atom such as fluorine, chlorine, bromine or iodine.
R2 and R3 may be the same or different and each is an alkyl group having 1 to 6 carbon atoms, an alicyclic group having 5 to 7 carbon atoms, or a phenyl group which may have one or more substituents. Preferably, R2 and R3 may be the same and different and each is a lower alkyl group having 1 to 4 carbon atoms, an alicyclic group having 6 carbon atoms, or a phenyl group.
Specific examples of R2 and R3 include an alkyl group having 1 to 6 carbon atoms, such as methyl, ethyl, propyl, isopropyl, n-butyl, tert-butyl, isobutyl, sec-butyl, pentyl or hexyl; an alicyclic group having 5 to 7 carbon atoms, such as cyclopentyl, cyclohexyl or cycloheptyl; a phenyl group which may have one or more substitutents, for example, a lower alkyl group having 1 to 4 carbon atoms, such as methyl, ethyl, propyl, isopropyl, n-butyl, tert-butyl, isobutyl or sec-butyl, a lower alkoxy group having 1 to 4 carbon atoms, such as methoxy, ethoxy, propoxy or butoxy, a di(lower alkyl)amino group in which each alkyl has 1 to 3 carbon atoms, such as dimethylamino, diethylamino or dipropylamino, or a halogen atom such as fluorine, chlorine, bromine or iodine.
R4 , R5, R6, and R7 may be the same or different and each is an alkyl group having 1 to 6 carbon atoms, an alicyclic group having 5 to 7 carbon atoms, a phenyl group which may have one or more substituents, an alkoxy group having 1 to 6 carbon atoms, a dialkylamino group in which each alkyl has 1 to 3 carbon atoms, a halogen atom, a benzyl group, a naphthyl group, or a halogen-substituted lower alkyl group having 1 or 2 carbon atoms, provided that R4 and R5 taken together and/or R6 and R7 taken together represent a fused benzene ring, a substituted fused benzene ring, a trimethylene group, a tetramethylene group, or a methylenedioxy group; and p, q, r, and s each is 0 to 5, provided that p+q and r+s each is in the range of from 0 to 5. Preferably, R4 , R5 , R6, and R7 may be the same or different and each is a lower alkyl group having 1 to 4 carbon atoms, a lower alkoxy group having 1 to 4 carbon atoms, a di(lower alkyl)amino group in which each alkyl has 1 or 2 carbon atoms, or a halogen atom, provided that R4 and R5 may and R6 and R7 may together represent a fused benzene ring or a methylenedioxy group. Furthermore, p, q, r, and s each preferably is 0 to 2.
Specific examples of R4, R5, R6, and R7 include a hydrogen atom; a lower alkyl group having 1 to 4 carbon atoms, such as methyl, ethyl, propyl, isopropyl, n-butyl, tert-butyl, isobutyl or sec-butyl; an alicyclic group having 5 to 7 carbon atoms, such as cyclopentyl, cyclohexyl or cycloheptyl; a phenyl group which may have one or more substitutents, for example, a lower alkyl group having 1 to 4 carbon atoms, such as methyl, ethyl, propyl, isopropyl, n-butyl, tert-butyl, isobutyl or sec-butyl, a lower alkoxy group having 1 to 4 carbon atoms, such as methoxy, ethoxy, propoxy or butoxy, a di(lower alkyl)amino group in which each alkyl has 1 to 3 carbon atoms, such as dimethylamino, diethylamino or dipropylamino, or a halogen atom such as fluorine, chlorine, bromine or iodine; a lower alkoxy group having 1 to 4 carbon atoms, such as methoxy, ethoxy, propoxy, or butoxy; a di(lower alkyl)amino group in which each alkyl has 1 to 3 carbon atoms, such as dimethylamino, diethylamino or dipropylamino; a halogen atom such as fluorine, chlorine, bromine or iodine; a benzyl group; a naphthyl group; or a halogen-substituted lower alkyl group having 1 or 2 carbon atoms, such as trifluoromethyl, trichloromethyl, or tribromomethyl.
Furthermore, R4 and R5 taken together and/or R6 and R7 taken together represent a fused benzene ring, a substituted fused benzene ring, a trimethylene group, a tetramethylene group, or a methylenedioxy group.
Preferred examples of the 2,2-(diaryl)vinylphosphine compound of the invention, which is represented by general formula (1) described above, include the compounds shown in Tables 1 to 17 given below. However, the compound of the invention should not be construed as being limited to these examples.
The abbreviations used in Tables 1 to 17 have the following meanings, respectively. The abbreviations used in compound names appearing hereinafter have the same meanings. The numeral preceding the abbreviation or symbol for a substituent indicates the position of the substituent on the phenyl group (for example, 4-Me means a methyl substituent bonded to the 4-position carbon atom of the phenyl group).
Me methyl
Et ethyl
nPr n-propyl
iPr isopropyl
nBu n-butyl
iBu isobutyl
tBu tert-butyl
MeO methoxy
EtO ethoxy
F fluorine atom
Cl chlorine atom
Br bromine atom
Me2N dimethylamino
Et2N diethylamino
CyPe cyclopentyl
CyHx cyclohexyl
Ph phenyl
p-Tol p-tolyl
Xy 2,4-xylyl
2,3-benzene means that the substituents fuse with the benzene ring to form an xcex1-naphthyl group.
3,4-benzene means that the substituents fuse with the benzene ring to form a xcex2-naphthyl group.
The compound (1) of the invention is produced, for example, by the process shown by the following reaction formula. 
(In the formula, R1, R2, R3, R4, R5, R6, R7, p, q, r, and s have the same meanings as defined above; X is a halogen atom; and R is a lower alkyl group having 1 to 4 carbon atoms.)
Specifically, the process comprises the following five steps as shown above.
First Step: A step in which an alcohol compound (8) is obtained by a) a method comprising the reaction of a diaryl ketone (3) with a Grignard reagent (5), or by b) a method comprising the reaction of an ester (4) with a Grignard reagent (6) and/or another Grignard reagent.
Second Step: A step in which the alcohol compound (8) is dehydrated with an acid catalyst (e.g., p-toluenesulfonic acid) to obtain a vinyl compound (9).
Third Step: A step in which the vinyl compound (9) is caused to addition reaction of a halogen to thereby obtain a dihalide compound (10).
Fourth Step: A step in which the dihalide compound (10) is subjected to dehydrohalogenation optionally in the presence of a base (e.g., pyridine) to obtain a vinyl halide compound (11).
Fifth Step: A step in which lithium metal, an alkyllithium, or magnesium metal is caused to act on the vinyl halide compound (11) to prepare a vinyllithium compound or vinyl Grignard reagent and this reaction product is subjected to coupling reaction with a phosphorus halide compound (12) to obtain a 2,2-(diaryl)vinylphosphine compound (1) of the invention.
In the compound (3) to compound (10) in the formula shown above, R1, R2, R3, R4, R5, R6, R7, p, q, r, and s have the same meanings as defined above; X is a halogen atom; and R in the compound (4) is a lower alkyl group having 1 to 4 carbon atoms.
Examples of R1, R2, R3, R4, R5, R6, and R7 include the same groups and atoms as enumerated above.
Examples of X include a halogen atom such as fluorine, chlorine, bromine or iodine.
Examples of R include a lower alkyl group having 1 to 4 carbon atoms such as methyl, ethyl, propyl, isopropyl, n-butyl, tert-butyl, isobutyl or sec-butyl.
As the diaryl ketone (3) and the ester (4) may be used a commercial diaryl ketone compound and a commercial ester compound (e.g., ones manufactured by Tokyo Kasei Kogyo Co., Ltd. and Nacalai Tesque, Inc.) without any treatment. Alternatively, the ketone (3) and ester (4) may be synthesized by known methods.
The Grignard reagents (5), (6), and (7) may be ones prepared by a known method from corresponding halogen compounds on the market or from halogen compounds synthesized by a known method.
For conducting the first step, in which an alcohol compound (8) is obtained by a) a method comprising the reaction of a diaryl ketone (3) with a Grignard reagent (5), or by b) a method comprising the raction of an ester (4) with a Grignard reagent (6) and/or another Grignard reagent, an ordinary Grignard reaction can be used.
In the Grignard reaction by method a), an alcohol compound (8) can be obtained by the reaction of a diaryl ketone (3) with a Grignard reagent (5).
The amount of the Grignard reagent (5) to be used is preferably about from 0.5 to 10 mol, more preferably about from 0.8 to 3.0 mol, per mol of the diaryl ketone (3).
Examples of reaction solvents include ether solvents such as diethyl ether, diisopropyl ether, tetrahydrofuran, dimethoxyethane, dioxane, and 1,3-dioxolane. Preferred of these are diethyl ether and tetrahydrofuran. Such a solvent may be used in an amount of preferably about from 1.0 to 80 times by volume, more preferably about from 2.0 to 30 times by volume, the amount of the diaryl ketone (3).
Appropriate additives may be added in conducting in this reaction in order to accelerate the reaction. Examples of the additives include cesium trichloride, zinc chloride, zinc bromide, copper chloride, copper bromide, copper iodide, aluminum trichloride, and titanium tetrachloride. Preferred of these are cesium trichloride, copper chloride, copper bromide, and copper iodide. The amount of such additives to be used is preferably about from 0.01 to 10 mol, more preferably about from 0.05 to 3.0 mol, per mol of the diaryl ketone (3).
This reaction is usually conducted under an inert gas atmosphere such as nitrogen gas or argon gas. In this reaction, the reaction time is generally about from 10 minutes to 30 hours, preferably about from 30 minutes to 12 hours, and the reaction temperature is generally about from xe2x88x9220 to 100xc2x0 C., preferably about from 0 to 70xc2x0 C. Although such conditions can be used to carry out the reaction, they may be suitably varied according to the kinds and amounts of the diaryl ketone (3) and Grignard reagent (5) to be used, etc.
In the Grignard reaction by method b), an alcohol compound (8) can be obtained by the reaction of an ester (4) with a Grignard reagent (6) and/or another Grignard reagent.
The amount of the Grignard reagents (6) and (7) to be used is preferably about from 1.0 to 10 mol, more preferably about from 1.6 to 4.8 mol, per mol of the ester (4).
Examples of reaction solvents include ether solvents such as diethyl ether, diisopropyl ether, tetrahydrofuran, dimethoxyethane, dioxane, and 1,3-dioxolane. Preferred of these are diethyl ether and tetrahydrofuran. Such a solvent may be used in an amount of preferably about from 1.0 to 50 times by volume, more preferably about from 4.0 to 10 times by volume, the amount of the ester (4).
Appropriate additives may be added in conducting the reaction in order to accelerate the reaction. Examples of the additives include cesium trichloride, zinc chloride, zinc bromide, copper chloride, copper bromide, copper iodide, aluminum trichloride, and titanium tetrachloride. Preferred of these are cesium trichloride, copper chloride, copper bromide, and copper iodide. The amount of such additives to be used is preferably about from 0.01 to 10 mol, more preferably about from 0.05 to 3.0 mol, per mol of the ester (4).
This reaction is usually conducted under an inert gas atmosphere such as nitrogen gas or argon gas. In this reaction, the reaction time is generally about from 10 minutes to 30 hours, preferably about from 30 minutes to 8 hours, and the reaction temperature is generally about from xe2x88x9220 to 100xc2x0 C., preferably about from 0 to 70xc2x0 C. Although such conditions can be used to carry out the reaction, they may be suitably varied according to the kinds and amounts of the ester (4) and Grignard reagents (6) and (7) to be used, etc.
In each of a) and b) described above, an ordinary post-treatment is conducted after completion of the reaction, whereby the target compound can be obtained.
For conducting the second step, in which the alcohol compound (8) is dehydrated with an acid catalyst (e.g., p-toluenesulfonic acid) to obtain a vinyl compound (9), an ordinary dehydration reaction can be used.
Examples of the acid catalyst include hydrochloric acid, sulfuric acid, camphorsulfonic acid, benzenesulfonic acid, and p-toluenesulfonic acid. Preferred of these is p-toluenesulfonic acid. The amount of the acid catalyst to be used is preferably about from 0.0001 to 0.2 mol, more preferably about from 0.005 to 0.05 mol, per mol of the alcohol compound (8).
Examples of reaction solvents include aromatic hydrocarbons such as benzene, toluene, xylene, and chlorobenzene; and ether solvents such as diethyl ether, diisopropyl ether, tetrahydrofuran, dimethoxyethane, dioxane, and 1,3-dioxolane. Preferred of these are benzene, toluene, and xylene. Such a solvent may be used in an amount of preferably about from 1.0 to 50 times by volume, more preferably about from 2.0 to 20 times by volume, the amount of the alcohol compound (8).
This reaction is usually conducted under an inert gas atmosphere such as nitrogen gas or argon gas. In this reaction, the reaction time is generally about from 10 minutes to 30 hours, preferably about from 30 minutes to 8 hours, and the reaction temperature is generally about from 20 to 180xc2x0 C., preferably about from 70 to 140xc2x0 C. Although such conditions can be used to carry out the reaction, they may be suitably varied according to the kinds and amounts of the alcohol compound (8) and acid catalyst to be used, etc.
After completion of the reaction, an ordinary post-treatment is conducted, whereby the target compound can be obtained.
For conducting the third step, in which the vinyl compound (9) is caused to add a halogen to thereby obtain a dihalide compound (10), the ordinary halogen addition reaction to an olefin can be used.
Examples of the halogen include chlorine, bromine, and iodine, and bromine is preferred. The amount of the halogen to be used is preferably about from 0.5 to 2.0 mol, more preferably about from 0.8 to 1.2 mol, per mol of the vinyl compound (9).
Examples of reaction solvents include aromatic hydrocarbons such as benzene, toluene, xylene, and chlorobenzene; ether solvents such as diethyl ether, diisopropyl ether, tetrahydrofuran, dimethoxyethane, dioxane, and 1,3-dioxolane; and halogenated solvents such as dichloromethane, chloroform, carbon tetrachloride, dichloroethane, dibromomethane, and dibromoethane. Preferred of these are halogenated solvents such as dichloromethane, dichloroethane, chloroform, and carbon tetrachloride. Such a solvent may be used in an amount of preferably about from 0.2 to 50 times by volume, more preferably about from 0.5 to 20 times by volume, the amount of the vinyl compound (9).
This reaction is usually conducted under an inert gas atmosphere such as nitrogen gas or argon gas. In this reaction, the reaction time is generally about from 10 minutes to 24 hours, preferably about from 30 minutes to 8 hours, and the reaction temperature is generally about from xe2x88x9260 to 100xc2x0 C., preferably about from xe2x88x9230 to 50xc2x0 C. Although such conditions can be used to carry out the reaction, they may be suitably varied according to the kinds and amounts of the vinyl compound (9) and halogen to be used, etc.
After completion of the reaction, an ordinary post-treatment is conducted, whereby the target compound can be obtained.
For conducting the fourth step, in which the dihalide compound (10) is subjected to dehydrohalogenation optionally in the presence of a base to obtain a vinyl halide compound (11), an ordinary dehydrohalogenation reaction can be used.
Examples of the base include triethylamine, dimethylaniline, diethylaniline, pyridine, picoline, lutidine, ethylpyridine, quinoline, and isoquinoline. Preferred of these is pyridine. Such a base may be used in an amount of preferably about from 0.5 to 30 mol, more preferably about from 1.0 to 10 mol, per mol of the dihalide compound (10).
Examples of reaction solvents include aromatic hydrocarbons such as benzene, toluene, xylene, and chlorobenzene; and ether solvents such as diethyl ether, diisopropyl ether, tetrahydrofuran, dimethoxyethane, dioxane, and 1,3-dioxolane. Preferred of these are benzene, toluene, and xylene. Such a solvent may be used in an amount of preferably about from 0.2 to 30 times by volume, more preferably about from 0.5 to 10 times by volume, the amount of the dihalide compound (10).
This reaction is usually conducted under an inert gas atmosphere such as nitrogen gas or argon gas. In this reaction, the reaction time is generally about from 10 minutes to 30 hours, preferably about from 30 minutes to 16 hours, and the reaction temperature is generally about from 20 to 140xc2x0 C., preferably about from 60 to 110xc2x0 C. Although such conditions can be used to carry out the reaction, they may be suitably varied according to the kinds and amounts of the dihalide compound (10) and base to be used, etc.
After completion of the reaction, an ordinary post-treatment is conducted, whereby the target compound can be obtained.
For conducting the fifth step, in which lithium metal, an alkyllithium, or magnesium metal is caused to act on the vinyl halide compound (11) to prepare a vinyllithium compound or vinyl Grignard reagent and this reaction product is subjected to coupling reaction with a phosphorus halide compound (12) to obtain a 2,2-(diaryl)vinylphosphine compound (1) of the invention, use can be made of the ordinary coupling reaction of a lithium reagent or Grignard reagent with a phosphorus halide compound.
The amount of the lithium metal, alkyllithium, or magnesium metal to be used is preferably about from 0.5 to 3.0 mol, more preferably about from 0.8 to 1.5 mol, per mol of the vinyl halide compound (11).
The amount of the halogenated phosphorus compound (12) to be used is preferably about from 0.5 to 3.0 mol, more preferably about from 0.7 to 1.5 mol, per mol of the vinyl halide compound (11).
Examples of reaction solvents include ether solvents such as diethyl ether, diisopropyl ether, tetrahydrofuran, dimethoxyethane, dioxane, and 1,3-dioxolane. Preferred of these are diethyl ether and tetrahydrofuran. Such a solvent may be used in an amount of preferably about from 1.0 to 50 times by volume, more preferably about from 4.0 to 30 times by volume, the amount of the vinyl halide compound (11).
Appropriate additives may be added in conducting in this reaction in order to accelerate the reaction. Examples of the additives include copper chloride, copper bromide, copper iodide, copper triflate, copper cyanide, a copper iodide-dimethyl sulfide complex, a copper iodide-triphenylphosphine complex, and a copper iodide-tributylphosphine complex. Preferred of these are copper chloride, copper bromide, and copper iodide. The amount of such additives to be used is preferably about from 0.01 to 10 mol, more preferably about from 0.05 to 3.0 mol, per mol of the vinyl halide compound (11).
This reaction is usually conducted under an inert gas atmosphere such as nitrogen gas or argon gas. In this reaction, the reaction time is generally about from 10 minutes to 40 hours, preferably about from 30 minutes to 24 hours, and the reaction temperature is generally about from xe2x88x92100 to 120xc2x0 C., preferably about from xe2x88x9280 to 80xc2x0 C. Although such conditions can be used to carry out the reaction, they may be suitably varied according to the kinds and amounts of the vinyl halide compound (11) and phosphorus halide compound (12) to be used, etc.
After completion of the reaction, an ordinary post-treatment is conducted, whereby the target compound can be obtained.
The compound (1) of the invention thus obtained serves as a ligand to form a palladium-phosphine catalyst in cooperation with a palladium compound.
The palladium compound to be used as a catalyst precursor for forming the palladium-phosphine catalyst is not particularly limited. However, salts or complexes of palladium having a valence of 4, 2, or 0 are mainly used.
Specific examples of the palladium compound include compounds of tetravalent palladium, such as sodium hexachloropalladate(IV) tetrahydrate and potassium hexachloropalladate(IV), compounds of bivalent palladium, such as palladium(II) chloride, palladium(II) bromide, palladium (II) acetate, palladium(II) acetylacetonate, dichlorobis(benzonitrile)palladium(II), dichlorobis(acetonitrile)palladium(II), dichlorobis(triphenylphosphine)palladium(II), dichlorotetraamminepalladium(II), dichloro(cycloocta-1,5-diene)palladium(II), palladium(II) trifluoroacetate, and xcfx80-allylpalladium(II) chloride dimer, and compounds of zero-valent palladium, such as tris(dibenzylideneacetone)dipalladium(0), tris(dibenzylideneacetone)dipalladium(0)-chloroform complex, and tetrakis(triphenylphosphine)palladium(0).
The palladium-phosphine catalyst obtained by causing a palladium compound to act on the novel 2,2-(diaryl)vinylphosphine compound (1) can be prepared, for example, by reacting the 2,2-(diaryl)vinylphosphine compound (1) with xcfx80-allylpalladium(II) chloride dimer according to the method described in Y. Uozumi and T. Hayashi, J. Am. Chem. Soc., 1991, Vol.113, p.9887.
The palladium-phosphine catalyst thus obtained by causing a palladium compound to act on the novel 2,2-(diaryl)vinylphosphine compound (1) of the invention can be used as a catalyst in the amination reaction or the carbon-carbon bond formation reaction in which an aryl compound having a leaving group is reacted with this reaction substance (an amine compound, an arylboric acid compound, an arylborate ester compound, or an alkyne compound) in the presence of a base.
The aryl compound having a leaving group in the invention is represented by general formula (2):
xe2x80x83ArX1xe2x80x83xe2x80x83(2)
(wherein Ar is an aryl group which may have one or more substituents or a heteroaryl group which may have one or more substituents; and X1 is a halogen atom, a trifluoromethanesulfonyloxy group, a methanesulfonyloxy group, or a toluenesulfonyloxy group).
The aryl compound (2) to be used in the invention is not particularly limited. Examples thereof include aryl bromides, aryl chlorides, aryl iodides, aryl fluorides, aryl trifluoromethanesulfonate, aryl methanesulfonate, aryl p-toluenesulfonate, and aryl halides having two or more halogen atoms.
Specific examples of the aryl compound (2) include: aryl bromides such as bromobenzene, o-bromoanisole, m-bromoanisole, p-bromoanisole, o-bromotoluene, m-bromotoluene, p-bromotoluene, o-bromophenol, m-bromophenol, p-bromophenol, 2-bromobenzotrifluoride, 3-bromobenzotrifluoride, 4-bromobenzotrifluoride, 1-bromo-2,4-dimethoxybenzene, 1-bromo-2,5-dimethoxybenzene, 2-bromophenethyl alcohol, 3-bromophenethyl alcohol, 4-bromophenethyl alcohol, 5-bromo-1,2,4-trimethylbenzene, 2-bromo-m-xylene, 2-bromo-p-xylene, 3-bromo-o-xylene, 4-bromo-o-xylene, 4-bromo-m-xylene, 5-bromo-m-xylene, 1-bromo-3-(trifluoromethoxy)benzene, 1-bromo-4-(trifluoromethoxy)benzene, 2-bromobiphenyl, 3-bromobiphenyl, 4-bromobiphenyl, 4-bromo-1,2-(methylenedioxy)benzene, 1-bromonaphthalene, 2-bromonaphthalene, 1-bromo-2-methylnaphthalene, 1-bromo-4-methylnaphthalene, 1,4-dibromonaphthalene, 4,4xe2x80x2-dibromobiphenyl, 2-bromothiophene, 3-bromothiophene, 2-bromopyridine, 3-bromopyridine, 4-bromopyridine, 9-bromophenanthrene, 2-bromofuran, and 3-bromofuran;
aryl chlorides such as chlorobenzene, o-chloroanisole, m-chloroanisole, p-chloroanisole, o-chlorotoluene, m-chlorotoluene, p-chlorotoluene, o-chlorophenol, m-chlorophenol, p-chlorophenol, 2-chlorobenzotrifluoride, 3-chlorobenzotrifluoride, 4-chlorobenzotrifluoride, 1-chloro-2,4-dimethoxybenzene, 1-chloro-2,5-dimethoxybenzene, 2-chlorophenethyl alcohol, 3-chlorophenethyl alcohol, 4-chlorophenethyl alcohol, 5-chloro-1,2,4-trimethylbenzene, 2-chloro-m-xylene, 2-chlorop-xylene, 3-chloro-o-xylene, 4-chloro-o-xylene, 4-chloro-m-xylene, 5-chloro-m-xylene, 1-chloro-3-(trifluoromethoxy)benzene, 1-chloro-4-(trifluoromethoxy)benzene, 2-chlorobiphenyl, 3-chlorobiphenyl, 4-chlorobiphenyl, 1-chloronaphthalene, 2-chloronaphthalene, 1-chloro-2-methylnaphthalene, 1-chloro-4-methylnaphthalene, 1,4-dichloronaphthalene, 4,4xe2x80x2-dichlorobiphenyl, 2-chlorothiophene, 3-chlorothiophene, 2-chloropyridine, 3-chloropyridine, 4-chloropyridine, 9-chlorophenanthrene, 2-chlorofuran, and 3-chlorofuran;
aryl iodides such as iodobenzene, o-iodoanisole, m-iodoanisole, p-iodoanisole, o-iodotoluene, m-iodotoluene, p-iodotoluene, o-iodophenol, m-iodophenol, p-iodophenol, 2-iodobenzotrifluoride, 3-iodobenzotrifluoride, 4-iodobenzotrifluoride, 1-iodo-2,4-dimethoxybenzene, 1-iodo-2,5-dimethoxybenzene, 2-iodophenethyl alcohol, 3-iodophenethyl alcohol, 4-iodophenethyl alcohol, 5-iodo-1,2,4-trimethylbenzene, 2-iodo-m-xylene, 2-iodo-p-xylene, 3-iodo-o-xylene, 4-iodo-o-xylene, 4-iodo-m-xylene, 5-iodom-xylene, 1-iodo-3-(trifluoromethoxy)benzene, 1-iodo-4(trifluoromethoxy)benzene, 2-iodobiphenyl, 3-iodobiphenyl, 4-iodobiphenyl, 1-iodonaphthalene, 2-iodonaphthalene, 1-iodo-2-methylnaphthalene, 1-iodo-4-methylnaphthalene, 1,4-diiodonaphthalene, 4,4xe2x80x2-diiodobiphenyl, 2-iodothiophene, 3-iodothiophene, 2-iodopyridine, 3-iodopyridine, 4-iodopyridine, 9-iodophenanthrene, 2-iodofuran, and 3-iodofuran;
aryl fluorides such as fluorobenzene, o-fluoroanisole, m-fluoroanisole, p-fluoroanisole, o-fluorotoluene, m-fluorotoluene, p-fluorotoluene, o-fluorophenol, m-fluorophenol, p-fluorophenol, 2-fluorobenzotrifluoride, 3-fluorobenzotrifluoride, 4-fluorobenzotrifluoride, 1-fluoro-2,4-dimethoxybenzene, 1-fluoro-2,5-dimethoxybenzene, 2-fluorophenethyl alcohol, 3-fluorophenethyl alcohol, 4-fluorophenethyl alcohol, 5-fluoro-1,2,4-trimethylbenzene, 2-fluoro-m-xylene, 2-fluoro-p-xylene, 3-fluoro-o-xylene, 4-fluoro-o-xylene, 4-fluoro-m-xylene, 5-fluoro-m-xylene, 1-fluoro-3-(trifluoromethoxy)benzene, 1-fluoro-4-(trifluoromethoxy)benzene, 2-fluorobiphenyl, 3-fluorobiphenyl, 4-fluorobiphenyl, 4-fluoro-1,2-(methylenedioxy) benzene, 1-fluoronaphthalene, 2-fluoronaphthalene, 1-fluoro-2-methylnaphthalene, 1-fluoro4-methylnaphthalene, 1,4-difluoronaphthalene, 4,4xe2x80x2-difluorobiphenyl, 2-fluorothiophene, 3-fluorothiophene, 2-fluoropyridine, 3-fluoropyridine, 4-fluoropyridine, 9-fluorophenanthrene, 2-fluorofuran, and 3-fluorofuran;
aryl trifluoromethanesulfonate such as trifluoromethanesulfonyloxybenzene, o-trifluoromethanesulfonyloxyanisole, m-trifluoromethanesulfonyloxyanisole, p-trifluoromethanesulfonyloxyanisole, o-trifluoromethanesulfonyloxytoluene, m-trifluoromethanesulfonyloxytoluene, p-trifluoromethanesulfonyloxytoluene, o-trifluoromethanesulfonyloxyphenol, m-trifluoromethanesulfonyloxyphenol, p-trifluoromethanesulfonyloxyphenol, 2-trifluoromethanesulfonyloxybenzotrifluoride, 3-trifluoromethanesulfonyloxybenzotrifluoride, 4-trifluoromethanesulfonyloxybenzotrifluoride, 1-trifluoromethanesulfonyloxy-2,4-dimethoxybenzene, 1-trifluoromethanesulfonyloxy-2,5-dimethoxybenzene, 2-trifluoromethanesulfonyloxyphenethyl alcohol, 3-trifluoromethanesulfonyloxyphenethyl alcohol, 4-trifluoromethanesulfonyloxyphenethyl alcohol, 5-trifluoromethanesulfonyloxy-1,2,4-trimethylbenzene, 2-trifluoromethanesulfonyloxy-m-xylene, 2-trifluoromethanesulfonyloxy-p-xylene, 3-trifluoromethanesulfonyloxy-o-xylene, 4-trifluoromethanesulfonyloxy-o-xylene, 4-trifluoromethanesulfonyloxy-m-xylene, 5-trifluoromethanesulfonyloxy-m-xylene, 1-trifluoromethanesulfonyloxy-3-(trfluoromethoxy)benzene, 1-trifluoromethanesulfonyloxy-4-(trifluoromethoxy)benzene, 2-trifluoromethanesulfonyloxybiphenyl, 3-trifluoromethanesulfonyloxybiphenyl, 4-trifluoromethanesulfonyloxybiphenyl, 4-trifluoromethanesulfonyloxy-1,2- (methylenedioxy) benzene, 1-trifluoromethanesulfonyloxynaphthalene, 2-trifluoromethanesulfonyloxynaphthalene, 1-trifluoromethanesulfonyloxy-2-methylnaphthalene, 1-trifluoromethanesulfonyloxy-4-methylnaphthalene, 1,4-ditrifluoromethanesulfonyloxynaphthalene, 4,4xe2x80x2-ditrifluoromethanesulfonyloxybiphenyl, 2-trifluoromethanesulfonyloxythiophene, 3-trifluoromethanesulfonyloxythiophene, 2-trifluoromethanesulfonyloxypyridine, 3-trifluoromethanesulfonyloxypyridine, 4-trifluoromethanesulfonyloxypyridine, 9-trifluoromethanesulfonyloxyphenanthrene, 2-trifluoromethanesulfonyloxyfuran, and 3-trifluoromethanesulfonyloxyfuran;
aryl methanesulfonate such as methanesulfonyloxybenzene, o-methanesulfonyloxyanisole, m-methanesulfonyloxyanisole, p-methanesulfonyloxyanisole, o-methanesulfonyloxytoluene, m-methanesulfonyloxytoluene, p-methanesulfonyloxytoluene, o-methanesulfonyloxyphenol, m-methanesulfonyloxyphenol, p-methanesulfonyloxyphenol, 2-methanesulfonyloxybenzotrifluoride, 3-methanesulfonyloxybenzotrifluoride, 4-methanesulfonyloxybenzotrifluoride, 1-methanesulfonyloxy-2,4-dimethoxybenzene, 1-methanesulfonyloxy-2,5-dimethoxybenzene, 2-methanesulfonyloxyphenethyl alcohol, 3-methanesulfonyloxyphenethyl alcohol, 4-methanesulfonyloxyphenethyl alcohol, 5-methanesulfonyloxy-1,2,4-trimethylbenzene, 2-methanesulfonyloxy-m-xylene, 2-methanesulfonyloxy-p-xylene, 3-methanesulfonyloxy-o-xylene, 4-methanesulfonyloxy-o-xylene, 4-methanesulfonyloxy-mxylene, 5-methanesulfonyloxy-m-xylene, 1-methanesulfonyloxy-3-(trifluoromethoxy)benzene, 1-methanesulfonyloxy-4-(trifluoromethoxy)benzene, 2-methanesulfonyloxybiphenyl, 3-methanesulfonyloxybiphenyl, 4-methanesulfonyloxybiphenyl, 4-methanesulfonyloxy-1,2(methylenedioxy)benzene, 1-methanesulfonyloxynaphthalene, 2-methanesulfonyloxynaphthalene, 1-methanesulfonyloxy-2-methylnaphthalene, 1-methanesulfonyloxy-4-methylnaphthalene, 1,4-dimethanesulfonyloxynaphthalene, 4,4xe2x80x2-dimethanesulfonyloxybiphenyl, 2-methanesulfonyloxythiophene, 3-methanesulfonyloxythiophene, 2-methanesulfonyloxypyridine, 3-methanesulfonyloxypyridine, 4-methanesulfonyloxypyridine, 9-methanesulfonyloxyphenanthrene, 2-methanesulfonyloxyfuran, and 3-methanesulfonyloxyfuran; and
aryl p-toluenesulfonate such as p-toluenesulfonyloxybenzene, o-(p-toluenesulfonyloxy)anisole, m-(p-toluenesulfonyloxy)anisole, p-(p-toluenesulfonyloxy)anisole, o-(p-toluenesulfonyloxy)toluene, m-(p-toluenesulfonyloxy)toluene, p-(p-toluenesulfonyloxy)toluene, o-(p-toluenesulfonyloxy)phenol, m-(p-toluenesulfonyloxy)phenol, p-(p-toluenesulfonyloxy)phenol, 2-(p-toluenesulfonyloxy)benzotrifluoride, 3-(p-toluenesulfonyloxy)benzotrifluoride, 4-(p-toluenesulfonyloxy)benzotrifluoride, 1-(p-toluenesulfonyloxy)-2,4-dimethoxybenzene, 1-(p-toluenesulfonyloxy)-2,5-dimethoxybenzene, 2-(p-toluenesulfonyloxy)phenethyl alcohol, 3-(p-toluenesulfonyloxy)phenethyl alcohol, 4-(p-toluenesulfonyloxy)phenethyl alcohol, 5-(p-toluenesulfonyloxy)-1,2,4-trimethylbenzene, 2-(p-toluenesulfonyloxy)-m-xylene, 2-(p-toluenesulfonyloxy)-p-xylene, 3-(p-toluenesulfonyloxy)-o-xylene, 4-(p-toluenesulfonyloxy)-o-xylene, 4-(p-toluenesulfonyloxy)-m-xylene, 5-(p-toluenesulfonyloxy)-m-xylene, 1-(p-toluenesulfonyloxy)-3-(trifluoromethoxy)benzene, 1-(p-toluenesulfonyloxy)-4-(trifluoromethoxy)benzene, 2-(p-toluenesulfonyloxy)biphenyl, 3-(p-toluenesulfonyloxy)biphenyl, 4-(p-toluenesulfonyloxy)biphenyl, 4-(p-toluenesulfonyloxy)-1,2-(methylenedioxy)benzene, 1-(p-toluenesulfonyloxy)naphthalene, 2-(p-toluenesulfonyloxy)naphthalene, 1-(p-toluenesulfonyloxy)-2-methylnaphthalene, 1-(p-toluenesulfonyloxy)-4-methylnaphthalene, 1,4-di(p-toluenesulfonyloxy)naphthalene, 4,4xe2x80x2-di(p-toluenesulfonyloxy)biphenyl, 2-(p-toluenesulfonyloxy)thiophene, 3-(p-toluenesulfonyloxy)thiophene, 2-(p-toluenesulfonyloxy)pyridine, 3-(p-toluenesulfonyloxy)pyridine, 4-(p-toluenesulfonyloxy)pyridine, 9-(p-toluenesulfonyloxy)phenanthrene, 2-(p-toluenesulfonyloxy)furan, and 3-(p-toluenesulfonyloxy)furan.
Other examples of aryl halides which can be used in the invention include aryl halides having two or more halogen atoms, such as 1,2-dibromobenzene, 1,3-dibromobenzene, 1,4-dibromobenzene, 9,10-dibromoanthracene, 9,10-dichloroanthracene, 1-bromo-2-fluorobenzene, 1-bromo-3-fluorobenzene, 1-bromo-4-fluorobenzene, 2-bromo-chlorobenzene, 3-bromo-chlorobenzene, 4-bromo-chlorobenzene, 2-bromo-5-chlorotoluene, 3-bromo-4-chlorobenzotrifluoride, 5-bromo-2-chlorobenzotrifluoride, 1-bromo-2,3-dichlorobenzene, 1-bromo-2,6-dichlorobenzene, 1-bromo-3,5-dichlorobenzene, 2-bromo-4-fluorotoluene, 2-bromo-5-fluorotoluene, 3-bromo-4-fluorotoluene, 4-bromo-2-fluorotoluene, and 4-bromo-3-fluorotoluene.
Examples of the amine compound to be used in the invention include primary amines, secondary amines, imines, and amides.
The primary amines are not particularly limited. Examples thereof include aliphatic primary amines such as ethylamine, propylamine, butylamine, isobutylamine, tertbutylamine, pentylamine, cyclopentylamine, hexylamine, cyclohexylamine, heptylamine, and octylamine; and aromatic primary amines such as aniline, o-fluoroaniline, mfluoroaniline, p-fluoroaniline, o-anisidine, m-anisidine, p-anisidine, o-toluidine, m-toluidine, p-toluidine, 2-naphthylamine, 2-aminobiphenyl, 4-aminobiphenyl, 3,4-methylenedioxyaniline, m-xylidine, and p-xylidine.
The secondary amines are not particularly limited. Examples thereof include cyclic secondary amines such as piperazine, 2-methylpiperazine, homopiperazine, N-methylhomopiperazine, 2,6-dimethylpiperazine, N-methylpiperazine, N-ethylpiperazine, N-ethoxycarbonylpiperazine, N-benzylpiperazine, morpholine, 2,6-dimethylmorpholine, piperidine, 2,6-dimethylpiperidine, 3,3-dimethylpiperidine, 3,5-dimethylpiperidine, 2-ethylpiperidine, 4-piperidone, pyrrolidine, 2,5-dimethylpyrrolidine, carbazole, indole, and indoline; and noncyclic secondary amines such as dimethylamine, diethylamine, and other noncyclic secondary amines which may have one or more substituents on the aromatic ring(s), such as N-methylaniline, N-ethylaniline, N-methylbenzylamine, N-methylphenethylamine, and diphenylamine derivatives.
The imines are not particularly limited. Examples thereof include benzophenonimine and 4,4xe2x80x2-dimethoxybenzophenoneimine.
The amides are not particularly limited. Examples thereof include 2-azetidinone (xcex2-propiolactam), xcex3-butyrolactam, xcex4-valerolactam, xcex5-caprolactam, acetamide, propionamide, cyclohexanecarboxamide, benzamide, N-methylformamide, N-methylacetamide, N-ethylacetamide, N-methylcyclohexanecarboxamide, and N-methylbenzamide.
The arylboric acid compounds and the arylborate ester compounds to be used in the invention are not particularly limited. Examples thereof include phenylboric acid, 4-methylphenylboric acid, 2-thienylboric acid, 2-furylboric acid, 2,3,4,5,6-pentafluorophenylboric acid, 2-fluorophenylboric acid, 3-fluorophnylboric acid, 4-fluorophenylboric acid, 2-chlorophenylboric acid, 3-chlorophenylboric acid, 4-chlorophenylboric acid, 2-bromophenylboric acid, 3-bromophenylboric acid, 4-bromophenylboric acid, 2-iodophenylboric acid, 3-iodophenylboric acid, 4-iodophenylboric acid, 2,4-difluorophenylboric acid, 2,5-difluorophenylboric acid, 2,6-difluorophenylboric acid, 3,4-difluorophenylboric acid, 3,5-difluorophenylboric acid, 4-trifluoromethylphenylboric acid, 3,5-bis(trifluoromethyl)phenylboric acid, 3-cyanophenylboric acid, 4-formylphenylboric acid, 4-methoxyphenylboric acid, 1-naphthylboric acid, 2-naphthylboric acid, ferrocenylboric acid, 4-hydroxyphenylboric acid, and the aryl borate ester compound (such as dimethyl, diethyl, dipropyl, diisoprpyl and pinacol ester) of the arylboric acid compound as defined above.
The arylalkyne compounds to be used in the invention are not particularly limited. Examples thereof include acetylene, propyne, 1-butyne, 1-pentyne, 1-hexyne, 1-heptyne, 1-octyne, phenylacetylene, 2-propyn-1-ol, 3-butyn-1-ol, 2-methyl-3-butyn-2-ol, 1-ethynyl-cyclohexanol, and trimethylsilylacetylene.
In the invention, the amine compound may be used so as to be present in the reaction system in an amount of from 0.1 to 50 mol per mol of the aryl compound (2) or in an amount of from 0.1 to 50 mol per mol of the leaving group on the ring structure of the aryl compound (2). However, from the standpoint of facilitating the recovery of the amine compound remaining unreacted, the amine compound is preferably used so as to be present in the reaction system in an amount of from 0.2 to 30 mol per mol of the aryl compound (2) or in an amount of from 0.2 to 60 mol per mol of the leaving group on the ring structure of the aryl compound (2).
In the invention, the aryl boric acid compound or aryl borate ester compound may be used so as to be present in the reaction system in an amount of from 0.1 to 50 mol per mol of the aryl compound (2) or in an amount of from 0.1 to 50 mol per of the leaving group on the ring structure of the aryl compound (2). However, from the standpoint of facilitating the recovery of the aryl boric acid compound or aryl borate ester compound remaining unreacted, the aryl boric acid compound or aryl borate ester compound is preferably used so as to be present in the reaction system in an amount of from 0.2 to 30 mol per mol of the aryl compound (2) or in an amount of from 0.2 to 60 mol per mol of the leaving group on the ring structure of the aryl compound (2).
In the invention, the alkyne compound may be used so as to be present in the reaction system in an amount of from 0.1 to 50 mol per mol of the aryl compound (2) or in an amount of from 0.1 to 50 mol per of the leaving group on the ring structure of the aryl compound (2). However, from the standpoint of facilitating the recovery of the alkyne compound remaining unreacted, the aryl boric acid compound or aryl borate ester compound is preferably used so as to be present in the reaction system in an amount of from 0.2 to 30 mol per mol of the aryl compound (2) or in an amount of from 0.2 to 60 mol per mol of the leaving group on the ring structure of the aryl compound (2).
The base to be used in the invention is not particularly limited, and may be selected from inorganic bases and/or organic bases. Preferred examples thereof include alkali metal fluorides such as lithium fluoride, sodium fluoride, potassium fluoride, rubidium fluoride, and cesium fluoride; alkali metal or alkaline earth metal carbonates such as lithium carbonate, sodium carbonate, potassium carbonate, rubidium carbonate, cesium carbonate, magnesium carbonate, calcium carbonate, and barium carbonate; alkali metal alkoxides such as sodium methoxide, sodium ethoxide, sodium phenoxide, potassium methoxide, potassium ethoxide, potassium phenoxide, lithium phenoxide, lithium tert-butoxide, sodium tert-butoxide, and potassium tert-butoxide; alkali metal phosphates such as lithium phosphate, potassium phosphate, and sodium phosphate; and tertiary amines such as triethylamine, tripropylamine, triisopropylamine, tributylamine, tricyclohexylamine; and secondary amines such as diethylamine, dipropylamine, diisopropylamine, dibutylamine, and dicyclohexylamine. Besides being added as it is to the reaction system, such as a base may be supplied to the reaction system by in situ preparing it from an alkali metal, alkali metal hydride, alkali metal hydroxide, or alkali metal phosphate and an alcohol.
The amount of the base to be used is preferably at least 0.5 mol per mol of the leaving group of the aryl compound (2). If the amount of the base is smaller than 0.5 mol, there are cases where the yield of an arylamine, a diaryl and an arylalkyne is reduced. Even when the base is added in large excess, the yield of an arylamine, a diaryl and an arylalkyne remains unchanged, resulting only in a complicated post-treatment after completion of the reaction. Consequently, the amount of the base to be added is more preferably in the range of from 1 to 5 mol.
The reaction according to the invention is usually conducted in the presence of an inert solvent. The solvent to be used is not particularly limited as long as it does not considerably inhibit the reaction. Examples thereof include aliphatic organic solvents such as pentane, hexane, heptane, and octane; alicyclic organic solvents such as cyclohexane and methylcyclohexane; aromatic organic solvents such as benzene, toluene, and xylene; ether type organic solvents such as diethyl ether, diisopropyl ether, dimethoxyethane, tetrahydrofuran, dioxane, and dioxolane; and acetonitrile, dimethylformamide, dimethyl sulfoxide, and hexamethylphosphoric triamide. Preferred of these are aromatic organic solvents such as benzene, toluene, and xylene and ether type organic solvents such as diethyl ether, dimethoxyethane, tetrahydrofuran, and dioxane.
In this reaction, the catalyst produces the same results when used by any of the following methods: a) a method in which a palladium compound; a base; an amine compound, an arylboric acid compound, an arylborate ester compound, or an alkyne compound; an aryl compound havng a leaving group; and the 2,2-(diaryl)vinylphosphine compound (1), which each has been described above, are charged into a reactor simultaneously; b) a method in which a palladium compound, the reaction substrate, and the 2,2-(diaryl)vinylphosphine compound (1) are separately charged into a reactor in the presence of a base; c) a method in which a palladium compound is mixed beforehand with the 2,2-(diaryl)vinylphosphine compound (1) in a reaction system to prepare a catalyst, and an aryl compound having a leaving group is then added to the reaction system in the presence of a base; and d) a method in which a palladium compound is mixed beforehand with the 2,2-(diaryl)vinylphosphine compound (1) to prepare a catalyst, and this catalyst and an aryl compound having a leaving group and this reaction substance are separately charged into a reactor.
The amount of the palladium compound to be used for the amination reaction or the carbon-carbon bond formation reaction is generally from 0.001 to 20 mol %, preferably from 0.01 to 5 mol %, based on this reaction substance (the amine compound, the arylboric acid compound, the arylborate ester compound, or the alkyne compound). The amount of the 2,2-(diaryl)vinylphosphine compound to be used for this reaction is generally from 0.1 to 10 times by mol, preferably from 1 to 5 times by mol, the amount of the palladium compound.
In the invention, a palladium compound and the 2,2-(diaryl)vinylphosphine compound (1) are indispensable.
The amination reaction or the carbon-carbon bond formation reaction according to the invention may be conducted at ordinary pressure under an inert gas atmosphere such as nitrogen or argon, or may be conducted at an elevated pressure.
The reaction according to the invention may be conducted at a temperature of generally from 10 to 300xc2x0 C., preferably from 20 to 200xc2x0 C.
Although the reaction time in the invention varies depending on the amounts of the aryl compound (2), this reaction substance (the amine compound, the arylboric acid compound, the arylborate ester compound, or the alkyne compound), base, palladium compound, and 2,2-(diaryl)vinylphosphine compound (1) and on the reaction temperature, it may be selected in the range of from several minutes to 72 hours.
After completion of the reaction, the reaction mixture is treated in an ordinary way, whereby the target compound can be obtained.
The novel 2,2-(diaryl)vinylphosphine compound of the invention, when used together with a palladium compound, serves as the catalyst of an amination reaction or a carbon-carbon bond formation reaction to show excellent performances. When this catalyst is used in the amination reaction or the carbon-carbon formation reaction of an aryl compound having a leaving group, an arylamine, a diaryl or an arylalkyne can be efficiently produced in a shorter time period than in the amination reaction or the carbon-carbon bond formation reaction with any conventional amination catalyst or any conventional carbon-carbon bond formation reaction catalyst. It is hence an excellent catalyst for industrial use.
The invention will be explained below in more detail by reference to Examples. However, the invention should not be construed as being limited by these Examples in any way.
In the Examples, properties were determined using the following apparatus.
1) 1H-NMR Spectrometry: Apparatus Type GEMINI 2000 (manufactured by Varian) or apparatus Type DRX-500 (manufactured by Varian).
Internal standard substance: tetramethylsilane
2) 31P-NMR Spectrometry: Apparatus Type DRX-500 (manufactured by Bruker)
External standard substance: 85% phosphoric acid
3) 19F-NMR Spectrometry: Apparatus Type DRX-500 (manufactured by Bruker)
Internal standard substance: trifluoroacetic acid
4) Melting Point: Yanaco MP-500D (manufactured by Yanagimoto Shoji K.K.)
5) Gas Chromatograph: GC 353 (manufactured by GL Science)
Column: NB-1 (30 mxc3x970.25 mm) (manufactured by GL Science)
Internal standard substance: o-terphenyl or tridecane
6) Mass Spectrometry (MS):
Mass spectrometer M-80: Ionization voltage, 20 eV (manufactured by Hitachi Ltd.)